GoKawiilThe convenience of instant coffee masks a surprisingly difficult problem. Coffee’s appeal lies in the hundreds of volatile compounds that create its flavor and aroma, exactly the substances most likely to disappear during processing. Creating instant coffee required developing techniques to extract the soluble molecules in coffee from the insoluble plant matter without destroying the fragile compounds that make coffee worth drinking.
The first attempt at the drink was, by all accounts, terrible. In 1771, over two centuries after coffee reached Europe, Londoner John Dring filed a patent for a ‘coffee compound’. Dring’s method involved mixing ground coffee with butter and tallow, then heating the mixture on an iron plate until it thickened into a paste that could be shaped into cakes. These cakes were then dissolved in hot water to make coffee. The purpose of the animal fats isn’t entirely clear. They may have been intended to extract and carry soluble compounds from the coffee grounds or to preserve the ground coffee from oxidation. Whatever Dring’s aim, the method wasn’t commercially viable because the fats went rancid, causing the cakes to spoil quickly.
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During the mid-1800s, several firms produced instant coffees as thick liquid concentrates that could be reconstituted with water. In 1840, the Scottish company T & H Smith developed a ‘coffee essence’ by brewing coffee and reducing it to around a quarter of its original volume. This thick liquid was mixed with chicory extract and burnt sugar syrup, creating a molasses-like concentrate. One or two teaspoons mixed with boiling water made a drink, though it tasted more like coffee flavored molasses than proper coffee.
Another attempt came during the American Civil War. In 1832, President Andrew Jackson had replaced soldiers’ daily spirit rations with coffee beans and sugar. This created a heavy logistical burden for the army, with a 20-day supply for 100,000 troops weighing 250 tons, all needing transport by horse-drawn wagon. Roasting, grinding, and brewing coffee in the field was also time-consuming for soldiers.
In 1861, the Union Army began investigating instant coffee as a solution. They procured a coffee concentrate from the firm HA Tilden & Co, consisting of a mixture of thickened coffee and sweetened, condensed milk. This halved the weight and size of the coffee, but was unpopular with soldiers, who compared its consistency to axle grease.
These essences were made by boiling down brewed coffee to concentrate it. This damages the flavor, producing a bitter, unpleasant drink, hence the old saying that ‘coffee boiled is coffee spoiled’. That’s why they were syrups. Boiling away all the water to create a dry powder would have destroyed whatever coffee flavor remained. To make a viable instant coffee powder, producers needed a way to remove the water from brewed coffee without boiling it.
A spice merchant’s solution
The first genuine instant coffee powder emerged in 1889, created by David Strang, a spice merchant in Invercargill, New Zealand. He developed a ‘Dry Hot-Air’ method that removed water from coffee by blowing heated air over it, likely using a spice dryer he’d patented a few years earlier. While hot air dehydration had been used in France since 1795 to dehydrate foods like pasta for commercial sale, Strang was the first to apply it to coffee.
The method works by warming the air around the coffee rather than the coffee itself. Turning water into vapor requires energy, which evaporating water draws from the heated air passing over it. Because this energy comes from the air rather than the liquid, the coffee surface actually gets cooler as it evaporates. This keeps the liquid below boiling temperature even as it dries.
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